Here is my new bird I have been working on. 60" wingspan Katana. Blew up a set of 3dfoamy plans although the construction is quite different. Powered by a Hacker A30-16M/TP 3 cell 2100 Prolite. I was goning to prop it to pull around 300 watts to start with then go up from there and see how the battery likes it. 4 HS 81's, Electron 6. Current weight as shown in photo is 21 ozs with the motor. (No radio, landing gear or battery yet) Target weight is 32 ozs RTF with battery...shoundt be a problem but we will see...Wing is 2pc of 6mm depron laminated together with a very thin 1/2" carbon strap on the front and rear leading edge of the wing Shocky style. Strap is glued on with contact cement and then covered with reinforced tape. Turned out very stiff and will fly fine with out bracing alough I will probably add some any way. Lower fuse half is 2 pcs of 6mm depron laminated together. From the nose to the rear of the landing gear on the lower half of the fuse I sandwitched a pc of 1/8" plywood between the 2 pcs of 6 mm depron. This ties the circular plywood motor mount to the landing gear. I was going to bend up some aluminum .065 landing gear and bolt it to the plywood. Rear elevator has one carbon strap bonded to it for stiffness. Should be able to finish her up this sunday and give a flight report.

Just ran a few tests with a 12x3.8 APC slowfly prop. 300 watts on a not fully charged 2100 prolite. At any rate it was wanting to hover at 1/2 throttle during the brief test from my hand. I suppose if I need a little more thrust I could go with a 12X4.7 Slowfly but it really was pulling hard at WOT like it would have some pretty awesome vertical. The landing gear came out a little heavier than I thought at around 3 ozs with wheels and everything ready to mount. Oh well, looks like the all up weight will be around 34-35 ozs...still not bad for a 60" wingspan RTF weight.

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Next step is to stiffen up the tail by boxing in the lower section of the fuse. After that I need to hinge the rudder and paint. In this photo you can see wings are 2 pcs of 6mm depron and the aileron is 1 pc 6 mm depron. Tail is all 1 pc 6 mm depron.

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As promised she flew today. To sum it up in a nut shell, very familiar flying characteristics, but much much more stable even with a very reward CG. As you can notice in the video there is pretty much no wing rock visable. Very similar to the way my giant You-can-do flys during 'crow' mode. This was my second flight. Still very manuverable but she flys almost hands off like a trainer. All up weight came in at ...35 ozs... the shame! oh well, its not going to fall apart any time soon. Sorry the video work sucks, it was my girlfriends doing. But bad video is always better than no video! Havent tried anything other than the APC 12X3.8. Its interesting this prop will pull a 35 oz plane out of a hover. Obviously the bird did not yet make it to the paint shop. Couple of changes yet are in order, stiffer main gear, and thicker push rods. It was flying with the pushrod wire that shipps with the slow stick. Video is 1.8 meg not a bad download.

Yeah, im not quite sure what I was thinking on the landing? I guess I flew around a little too long at high alpha and forgot that 35 oz planes dont just float in! At any rate I have confirmed in my mind that airfoils do nothing but spoil the way an airplane flys.

I think I am going to build another one but this time without laminating the wings or fuse. I am pretty sure normal shocky construction will work just fine with 6 mm depron at 60". It for sure will need bracing from the lower fuse to the mid point of the wing with carbon rod, but that adds hardly any weight. If I can shed 6-8 ozs I will be happy.